Re: HP 7475 plotter

When hand etching I just use a extra fine permanent marker. But I
don't how well a plotter could handle it. I always had to pay
attention to the shape of the felt tip. I've free handed a .8mm
pitch 44 pin TQFP. That is an experience I hope never to repeat.
For slightly larger sizes though, just replacing a pen with a
permanent marker should work. Are the regular pens felt tip? You
could get a photo-etch board, draw the design with any ink, expose
the board and etch like any photoetch procedure.. (or just laser
print it to a clear sheet and expose...)

--- In CAD_CAM_EDM_DRO@yahoogroups.com, "turbulatordude
<davemucha@j...>" <davemucha@j...> wrote:

> I think this is getting off topic, but the CNC pcb etcher is a
> deffinate topic for this list.
>
> I thought of painting a pcb with dykem then just erasing it with

the

> plotter. drilling holes still poses the problem.
>
> Seems any head could be used to drill, the lighter the better as

that

> would put less pressure on the low powered steppers.
>
> DD
>
>
>
> --- In CAD_CAM_EDM_DRO@yahoogroups.com, Bill Higdon <w.higdon@a...>
> wrote:
> > Hey Dangerous Dave,
> > There was an article in on of the Ham magazines back in 1977 that
> did
> > this. The trick was to use one of the reillable non fiber pens.

You

> > replaced the Ink with a paint and used the paint as a resist.

I'll

> try
> > and find it for you. As formilling a PCB how about the disposable
> drill
> > air turbo\ine some of the dentists use?
> >
> > Bill Higdon
> > turbulatordude wrote:
> > > if you want another, let me know. I do not know if they work,
> but
> > > would be good for spare parts.
> > >
> > > BUT, if someone figured out how to hack these for SLOW speed to
> use
> > > as a PCB marker, or etcher they could be of good use.
> > >
> > > right now, there is a guy on e-bay with thing boards, 20 thou.
> that
> > > would probably about the thickness these could handle.
> > >
> > > Ideally, someone could make an interface that ran them from a

CNC

> > > package. drilling would be the problem as I see it.
> > >
> > > Dave
> > >
> > >
> > >
> > >
> > > --- In CAD_CAM_EDM_DRO@yahoogroups.com, Alan Marconett KM6VV
> > > <KM6VV@a...> wrote:
> > >
> > >>Hi Marv,
> > >>
> > >>Couldn't have been that much! I bought one in '84. Maybe

$1400

> > >
> > > LIST,
> > >
> > >>don't recall. I got in under an HP employee discount. I still
> have
> > >>mine. "PRINT" under most windows programs often offers a

variety

> of
> > >>printers, including HGPL, and you can usually select save as
> file.
> > >>Print to this file, then "copy" file to comm port.
> > >>
> > >>I can watch the plotter for hours! I had thought of getting
> > >
> > > another one
> > >
> > >>(surplus), and using the parts.
> > >>
> > >>Alan KM6VV
> > >>
> > >>
> > >>Marv Frankel wrote:
> > >>
> > >>>Jan,
> > >>> A number of years ago I used that model plotter at my
> > >>
> > > office, and if I
> > >
> > >>>remember correctly, it cost about $4,000 to $4,500. It was

just

> > >>
> > > great, until
> > >
> > >>>the inkjet plotters took over. Where a pen plotter took 45
> > >>
> > > minutes to do a
> > >
> > >>>large plot, the inkjet took about 5 minutes, and then along

came

> > >>
> > > the
> > >
> > >>>electrostatics, etc. etc. etc...........
> > >>>
> > >>>Marv Frankel
> > >>>Los Angeles